Simulated moving columns technique for enantioselective supercritical fluid chromatography.

abstract：:A chiral alkylglucoside surfactant, namely n-octyl-beta-D-maltopyranoside (OM), was evaluated in the enantiomeric separation of phenoxy acid herbicides. The enantiomeric resolution of the phenoxy acid herbicides could be manipulated readily by adjusting the surfactant concentration, ionic strength, pH, the percent org...

journal_title：Chirality

authors： Mechref Y,el Rassi Z

更新日期：1996-01-01 00:00:00

abstract：:The impact of crystalline forces on the solid-state circular dichroism (CD) spectrum of hypothemycin (), a biologically active molecule extracted from natural sources, has been analyzed by means of time-dependent density functional theory CD calculations. Input structures were extracted from the X-ray geometry of and ...

journal_title：Chirality

authors： Pescitelli G

更新日期：2012-09-01 00:00:00

abstract：:The enantiomerization and enantioselective bioaccumulation of metalaxyl by a single dose of exposure to Tenebrio molitor larvae under laboratory condition were studied by high-performance liquid chromatography tandem mass spectroscopy (HPLC-MS/MS) based on a ChiralcelOD-3R [cellulosetris-tris-(3, 5-dichlorophenyl-carb...

journal_title：Chirality

authors： Gao Y,Wang H,Qin F,Xu P,Lv X,Li J,Guo B

更新日期：2014-02-01 00:00:00

abstract：:We report here a sensitive method for the determination of the absolute configurations of primary amines using exciton-coupled circular dichroism (ECCD). The method works on a microgram scale by derivatization of chiral amines with quinoline chromophores. Complexation of the chiral ligands with metal ion fixes the geo...

journal_title：Chirality

authors： Zhang J,Holmes AE,Sharma A,Brooks NR,Rarig RS,Zubieta J,Canary JW

更新日期：2003-02-01 00:00:00

abstract：:A rapid and effective RP-UHPLC-DAD method for enantioseparation of three flavanones, i.e., flavanone, naringenin, and hesperetin, was developed and validated. Chromatographic separation of the analytes was performed using a Chiralpak AD-3R analytical column under reverse phase conditions with methanol as the mobile ph...

journal_title：Chirality

authors： Baranowska I,Hejniak J,Magiera S

更新日期：2016-02-01 00:00:00

abstract：:Flurbiprofen is a kind of nonsteroidal anti-inflammatory drug, which has been widely used in clinic for treatment of rheumatoid arthritis and osteoarthritis. It has been reported that S-flurbiprofen shows good performance on clinic anti-inflammatory treatment, while R-enantiomer almost has no pharmacological activitie...

journal_title：Chirality

authors： Cui X,Ding Q,Shan RN,He CH,Wu KJ

更新日期：2019-06-01 00:00:00

abstract：:The improvement of the biocatalytic reduction of 2-allyl-carboethoxy-cyclopentanone (2) to the corresponding cyclopentanol derivative (+)-(1R,2R)-(1) was accomplished employing baker's yeast in organic media. This chiral cyclopentanol derivative (1), analyzed by high resolution gas chromatography performed over beta-c...

journal_title：Chirality

authors： Fraga CA,Barreiro EJ,da Silva EF,dos Santos AR,KV Ramos MdaC,de Aquino Neto FR

更新日期：1997-01-01 00:00:00

abstract：:One- and two-color, mass selected R2PI spectra of the S(1)<--S(0) transitions in the bare (+)-(R)-1-phenyl-1-ethanol (E(R)) and its complexes with different solvent molecules (solv) (-)-(R)-2-butanol (B(R)) or (+)-(S)-2-butanol (B(S)) and (-)-(R)-2-butylamine (A(R)) or (+)-(S)-2-butylamine (A(S)), have been recorded a...

journal_title：Chirality

authors： Giardini Guidoni A,Piccirillo S,Scuderi D,Satta M,Di Palma TM,Speranza M,Filippi A,Paladini A

更新日期：2001-01-01 00:00:00

abstract：:Integrating spheres are widely used with UV-Vis and occasionally with infrared spectrophotometers to measure different types of samples, either in transmission mode (scattered transmission accessories) or in total/diffuse reflectance mode. We built a prototype sphere of the demountable type, which fits easily the samp...

journal_title：Chirality

authors： Castiglioni E,Albertini P

更新日期：2000-05-01 00:00:00

abstract：:Hornet silks adopt a variety of morphology such as fibers, sponge, films, and gels depending on the preparation methods. We have studied the conformation change of hornet silk proteins (Vespa mandarina) as regenerated films, using chiroptical spectrophotometer universal chiroptical spectrophotometer 1, which can measu...

journal_title：Chirality

authors： Kuroda R,Kameda T

更新日期：2018-05-01 00:00:00

abstract：:(R)-(+) and (S)-(-)-1-phenylethylamine have been shown to promote highly diastereoselective and complementary enantioselective formal [3 + 2]carbocyclization reactions between 2,3-butanedione and conjugated nitroalkenes with formation of enantiomerically rich 2-hydroxy-3-nitrocyclopentanone derivatives. The reactions ...

journal_title：Chirality

authors： Felluga F,Forzato C,Nitti P,Pitacco G,Prati F,Valentin E,Zangrando E

更新日期：2012-12-01 00:00:00

abstract：:Environmental enantioselectivity information is important to fate assessment of chiral contaminants. Warfarin, a rodenticide and prescription medicine, is a chiral chemical but used in racemic form. Little is known about its enantioselective behavior in the environment. In this study, enantioselective degradation of w...

journal_title：Chirality

authors： Lao W,Gan J

更新日期：2012-01-01 00:00:00

abstract：:Stereoselective high-performance liquid chromatographic separations of eight sterically constrained cyclic β-amino acid enantiomer pairs were carried out using the newly developed Cinchona alkaloid-based zwitterionic chiral stationary phases Chiralpak ZWIX(+) and ZWIX(-). The effects of the mobile phase composition, t...

journal_title：Chirality

authors： Ilisz I,Gecse Z,Lajkó G,Forró E,Fülöp F,Lindner W,Péter A

更新日期：2015-09-01 00:00:00

abstract：:The elusive epimerization process in the chiral butenolide moiety of Annonaceous acetogenins was examined under several sets of conditions commonly used for elimination leading to the alpha, beta-unsaturated lactone and the results provide practical guidance in choosing elimination conditions. ...

journal_title：Chirality

authors： Yu Q,Wu Y,Wu YL,Xia LJ,Tang MH

更新日期：2000-03-01 00:00:00

abstract：:The aim of this work was to establish structure-reactivity relationships between chiral aggregates (micelles, vesicles, and "pseudo-micelles" of amphiphilic dendrimers) and asymmetric induction. In water, micelles or vesicles formed with sugar-headed surfactants gave less than 10% ee in the reduction of prochiral keto...

journal_title：Chirality

authors： Rico-Lattes I I,Schmitzer A,Perez E,Lattes A

更新日期：2001-01-01 00:00:00

abstract：:Novel enantiopure 1,2,4-trizole-3-thiones containing a benzensulfonamide moiety were synthesized via multistep reaction sequence starting with D-phenylalanine methyl ester and L-phenylalanine ethyl ester as a source of chirality. The chemical structures of all compounds were characterized by elemental analysis, UV, IR...

journal_title：Chirality

authors： Başaran E,Karaküçük-Iyidoğan A,Schols D,Oruç-Emre EE

更新日期：2016-06-01 00:00:00

abstract：:Cyclodextrins that are indiscriminately carboxymethylated at the 2-, 3-, and 6-positions are used as chiral NMR solvating agents for cationic substrates with phenyl, naphthyl, pyridyl, indoline, and indole rings. Enantiodifferentiation with the alpha-, beta-, and gamma-cyclodextrin derivatives is compared. The carboxy...

journal_title：Chirality

authors： Provencher KA,Weber MA,Randall LA,Cunningham PR,Dignam CF,Wenzel TJ

更新日期：2010-03-01 00:00:00

abstract：:Novel chiral diisopropyl spiro bis(isoxazoline) ligands, anti-i-Pr-SPRIX and syn-i-Pr-SPRIX, were designed and synthesized. Their catalytic utility, X-ray crystallographic analyses, and complexation studies demonstrated the structural features of tetraisopropyl spiro bis(isoxazoline) ligand, i-Pr-SPRIX, which is a pro...

journal_title：Chirality

authors： Takenaka K,Lin X,Takizawa S,Sasai H

更新日期：2015-08-01 00:00:00

abstract：:Nine patients taking oral doses of 10 mg/12 h rac-pindolol as part of their treatment for hypertension in pregnancy were recruited for the study. Maternal and fetal gestational age ranged from 20-38 years and 28-41 weeks, respectively. Blood was collected from the umbilical cord vein and from the mother from zero to 1...

journal_title：Chirality

authors： Gonçalves PV,Matthes Ado C,Da Cunha SP,Lanchote VL

更新日期：2002-08-01 00:00:00

abstract：:A new colorimetric chiral sensor material consisting of three different functional sites such as chromophore (2,4-dinitrophenylazophenol dye), binding site (crown ether), and chiral barrier (3,3'-diphenyl-1,1'-binaphthyl group) was prepared and applied to the recognition of the two enantiomers of primary amino alcohol...

journal_title：Chirality

authors： Cho EN,Li Y,Kim HJ,Hyun MH

更新日期：2011-04-01 00:00:00

abstract：:In order to cope with the increasing number of publications on the separation of enantiomers by chromatography on a chiral stationary phase, the graphical molecular database CHIRBASE was created. In the present state, the database package covers information (structural, bibliographic, and chromatographic data) on liqu...

journal_title：Chirality

authors： Koppenhoefer B,Nothdurft A,Pierrot-Sanders J,Piras P,Popescu C,Roussel C,Stiebler M,Trettin U

更新日期：1993-01-01 00:00:00

abstract：:Six secondary phosphine oxides and their tautomeric equilibria as free ligands and in the presence of an equimolar amount of the chiral dirhodium complex Rh* are described and discussed. Discrimination of enantiomers is easily possible by inspecting the (31)P NMR resonances; some (1)H and (13)C NMR resonances are usef...

journal_title：Chirality

authors： Magiera D,Szmigielska A,Pietrusiewicz KM,Duddeck H

更新日期：2004-01-01 00:00:00

abstract：:Enantiopure 3-((R)- and 3-((S)-1-phenylethyl)-4-oxazoline-2-ones were evaluated as chiral building blocks for the divergent construction of heterocycles with stereogenic quaternary centers. The N-(R)- or N-(S)-1-phenylethyl group of these compounds proved to be an efficient chiral auxiliary for the asymmetric inductio...

journal_title：Chirality

authors： Santoyo BM,González-Romero C,Zárate-Zárate D,Hernández-Benitez RI,Pelayo V,Barrera E,Escalante CH,Fuentes-Benites A,Martínez-Morales G,López J,Vázquez MA,Delgado F,Jiménez-Vázquez HA,Tamariz J

更新日期：2019-09-01 00:00:00

abstract：:Vitamin E is an essential nutrient of still increasing economic importance. Vitamin E derivatives include many nonracemic chiral compounds whose chirooptical characterization is scarcely described in the literature. We report the CD spectra of delta-tocopherol and its unsaturated analog delta-tocotrienol. TDDFT calcul...

journal_title：Chirality

authors： Mazzini F,Pescitelli G,Di Bari L,Netscher T,Salvadori P

更新日期：2009-01-01 00:00:00

abstract：:In this computational study, we illustrate a method for computing phosphorescence and circularly polarized phosphorescence spectra of molecular systems, which takes into account vibronic effects including both Franck-Condon and Herzberg-Teller contributions. The singlet and triplet states involved in the phosphorescen...

journal_title：Chirality

authors： Egidi F,Fusè M,Baiardi A,Bloino J,Li X,Barone V

更新日期：2018-07-01 00:00:00

abstract：:Subcellular fractions of three human brain specimens were found to contain esterase activities which hydrolyzed racemic oxazepam 3-acetate (rac-OXA). All three human brain preparations were highly selective toward the S-enantiomer of rac-OXA. ...

journal_title：Chirality

authors： Yang SK,Huang A,Huang JD

更新日期：1993-01-01 00:00:00

abstract：:A molecular docking study, using molecular mechanics calculations with AutoDock and semi-empirical PM3 calculations, was used to predict the enantiodiscrimination of heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin (TMβCD) and ketoconazole (KTZ) enantiomers. A Density Functional Theory (DFT) single-point calculation at the...

journal_title：Chirality

authors： Arsad SR,Maarof H,Wan Ibrahim WA,Aboul-Enein HY

更新日期：2016-03-01 00:00:00

abstract：:(+/-)-Pantoprazole ((+/-)-PAN), (+/-)-5-(difluoromethoxy)-2-[[3.4-dimethoxy-2-pyridinyl)methyl]sul finyl]- 1H-benzimidazole) is a chiral sulfoxide that is used clinically as a racemic mixture. The disposition kinetics of (+)-PAN and (-)-PAN given separately has been studied in rats. Serum levels of (+)- and (-)-PAN an...

journal_title：Chirality

authors： Masubuchi N,Yamazaki H,Tanaka M

更新日期：1998-01-01 00:00:00

abstract：:Steady-state pharmacokinetics of indobufen (INDB) enantiomers administered as racemic INDB (rac-INDB) tablets and bleeding time were studied in patients. Two-hundred mg INDB tablets (Ibustrin) were administered twice daily for 7 days to obliterative atherosclerosis patients. Enantiospecific reversed phase (RP) HPLC wi...

journal_title：Chirality

authors： Glówka FK,Strzelecka D,Zapalski S

更新日期：2001-06-01 00:00:00

abstract：:In this review article we examine state-of-the-art techniques for the structural elucidation of organic compounds isolated from natural sources. In particular, we focus on the determination of absolute configuration (AC), perhaps the most challenging but inevitable step in the whole process, especially when newly isol...

journal_title：Chirality

authors： Pescitelli G,Kurtán T,Flörke U,Krohn K

更新日期：2009-01-01 00:00:00